1. Field of the Invention
The present invention broadly relates to electrical drive circuitry and, more particularly, is concerned with an electrical circuit for bi-directionally powering a reversible DC electric motor.
2. Description of the Prior Art
One type of prior art printer has a print stylus which is pivotable between print and nonprint positions relative to a print medium. Also, the stylus is laterally movable across the print medium through a printing cycle and a nonprinting return cycle.
When the print stylus is at its initial position for the start of printing, it is pivoted to its print position toward the print medium by operation of a DC motor which rotates a shaft coupled to the stylus. The stylus is then moved across the medium in a printing cycle, such as by rotation of a screw which mounts the stylus.
Once the printing cycle is completed, the motor is deactivated and a spring connected with the shaft counter-rotates the shaft which pivots the stylus to its nonprint position away from the print medium. The stylus is then moved back across the medium in a nonprinting cycle by reverse rotation of the screw. The motor is not reactivated again (which would overcome the bias of the spring) until the stylus has been returned back to its initial position.
While the above-described prior art printer, for the most part, functions satisfactorily, it is believed that improvement thereof in the movement of its print stylus between print and nonprint positions would be desirable.